Variable speed belt drive



FIG. 1 is a perspective view of a variable speed belt drive embodying our new design;

FIG. 2 is a top plan view thereof, the extension of the shaft on the right shown broken away to indicate indeterminate length;

FIG. 3 is an elevational view of the side opposite the side shown in FIG. 1; and

FIG. 4 is an elevational view of the end opposite the end shown in FIG. 1. 

The ornamental design for a variable speed belt drive, substantially as shown and described. 